In a philosophical context, the World is the whole of the physical Universe.
In a theological context, the World is the material or the profane sphere, as opposed to the celestial, spiritual, transcendent or sacred.
The World Population is the total number of Human‘s currently living. As of March 2017, it was estimated at 7.49 billion. The United Nations estimates it will further increase to 11.2 billion in the year 2100.